One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,5)(4,6)(7,8)(9,10,16,15)(11,13,17,12)(14,22,23,18)(19,20,24,21)(26,28)(27,33)(32,36)(35,39)(2,3)(6,7)(9,11)(10,13)(12,15)(14,19)(16,17)(18,21)(20,22)(23,24)(25,26,30,28)(27,31,33,34)(29,32,37,36)(35,38,39,40)(4,8)(6,7)(9,12,16,13)(10,17,15,11)(14,20,23,21)(18,24,22,19)(25,26,30,28)(27,31,33,34)(29,36,37,32)(35,40,39,38)(1,3,5,2)(4,7,8,6)(9,13,16,12)(10,17,15,11)(14,21,23,20)(18,24,22,19)(25,27)(26,31)(28,34)(29,35)(30,33)(32,38)(36,40)(37,39)(9,14,16,23)(10,18,15,22)(11,19,17,24)(12,20,13,21)(25,28,30,26)(27,34,33,31)(29,36,37,32)(35,40,39,38)(1,4)(2,6)(3,7)(5,8)(9,15,16,10)(11,12,17,13)(14,22,23,18)(19,20,24,21)(25,29,30,37)(26,32,28,36)(27,35,33,39)(31,38,34,40)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.